Related Experiment Video
Updated: Jun 5, 2026

Inverse Probability of Treatment Weighting (Propensity Score) using the Military Health System Data Repository and National Death Index
Published on: January 8, 2020
Patient risk factors for medical injury: a case-control study
A M Marbella1, P W Laud, K J Brasel
1Department of Family and Community Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA. amarbella@sbcglobal.net
Objective:
To determine risk factors of medical injury, defined as untoward injury from diagnostic or therapeutic healthcare interventions. Identifying risk factors for medical injuries could inform the development of preventive interventions.
Methods:
A hospital-based case-control study. Cases and controls were selected among patients discharged from a large Midwestern teaching hospital between 1 January 2003 and 31 December 2004. Cases (n=268) were selected in a three-step process. First, medical injuries in the discharge database were identified using the Wisconsin Medical Injury Prevention Programme Surveillance Criteria. Second, provisional cases were randomly chosen from patients flagged with a medical injury. Provisional controls were randomly selected from patients not flagged with a medical injury, matching for Diagnosis Related Group of the provisional cases. Third, a chart review determined ultimate case-control status. Severity of illness and risk of mortality were calculated using the All Patients Refined-Diagnosis Related Groups system. Zahn's comorbidity score was calculated. Conditional logistic regressions were run with injury status as the dependent variable.
Results:
Among the 268 cases, 47.8% were procedure-related injuries and 44.8% were medication-related injuries. Conditional logistic regressions found higher severity of illness and higher risks of mortality were related to risk of medical injury (OR 3.29 (95% CI 1.05 to 10.31) and OR 5.16 (95% CI 1.42 to 18.79), respectively). Additional regressions showed the Zahn comorbidity score related to the risk of medical injury (OR 1.63, 95% CI 1.31 to 2.02).
Conclusions:
Patients with higher severity of illness, higher risk of inpatient mortality and multiple comorbidities are at increased risk for a medical injury.
Related Concept Videos
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast, controlled...
Cellular Injury II: Classification
Factors Affecting the Risk of Infection
The integrity and count of the white blood cells help the body resist pathogens and fight infection. When impaired, it reduces the body's resistance to pathogens. The acidic pH levels of the gastrointestinal, genitourinary tracts, and skin create...
Drug Toxicity: Risk factors
Hazard Ratio
For example, in a clinical trial evaluating a...
Torts I
Intentional...
